Credit: Courtesy photo

“White Devil,” a new book by Bob Halloran that tells the real-life saga of a Dorchester orphan who rose through the ranks of Boston’s Chinese mafia in the 1990s, hits the bookstores next week — and the stranger-than-fiction tale may be headed to the big screen.

Halloran’s book tells the incredible story of John Willis, a 40-something gangster now serving 20 years in federal prison for selling oxycodone. Willis joined an Asian gang as a 16-year-old and muscled his way up the ranks to become the right-hand man of Ping On boss Bai Ming.

“The FBI called him Bac Gaui, White Devil,” Halloran said. “The Chinese are very suspicious of outsiders and they would not normally bring in a white kid. But John was innocent and polite. He adopted the Chinese and they adopted him.”

Orphaned at 14, two years later, Willis was working as a bouncer in a Kenmore Square bar when a young Chinese gangster got into a fight. Willis, who was huge for his age, came to his aide.

“The kid gave him a card with his name and phone number on it and told John, ‘If you ever need help, call me,’” said Halloran, who has written three previous books.

Freezing, hungry and with no place to stay in a snowstorm one night, Willis called the number.

“A car pulled up with six or seven Chinese guys in it and they brought him to a big house,” Halloran said. “Boom, he was in the gang. It happened that quickly.”

Because of his size and strength, Willis became a top enforcer for the Ping On and he moved up the ranks quickly. His bosses even sent him to New York to learn the ropes there, and when he returned to Boston, he became the bodyguard for the city’s top Asian gangster, Bai Ming.

“He learned to speak Chinese on his own, listening and repeating things he heard. That helped him rise through the ranks,” Halloran said. “He ended up sitting at the right hand of the boss.”

Ultimately, Bai Ming wanted out of the drug business, and Willis saw his chance. Soon he was running a multimillion-dollar oxycodone operation, running drugs from the pill mills in Florida up the East Coast.

“Ultimately, that led to his downfall,” Halloran said.

Halloran spent seven hours interviewing Willis at the federal prison in Cumberland, Md., for the book. Separately, Warner Bros. has the rights to Willis’ story and James Gray of “We Own the Night” fame is attached to write the script and direct.

Halloran said his agent is also in talks with three television production companies that are interested in the story.

“It could be a terrific movie and I’m anticipating that happening,” Halloran said. “But that’s the weird thing about the publishing world. You get an idea and almost 2 1/2 years later, a book comes out. Who knows how long it will take for a movie.”